Modification Of Acrylamide Hydrogels And Its Antimicrobial Properties

Bacterial infection has always threatened human health,especially in recent years,the epidemic of infectious diseases has taken a large number of human lives.According to the statistics of the World Health Organization,the number of deaths caused by infectious diseases has also firmly occupied the second largest cause of death in the world,which has also caused great impact on economic development.The overuse of antibiotics makes some bacteria resistant,making the treatment of bacterial infections more difficult,so the selection of antimicrobial agents is also very important.Hydrogel is undoubtedly one of the best choices for antimicrobial agents.Hydrogel has good biocompatibility.In treating wounds,it can promote wound healing effectively because of its similar characteristics with extracellular matrix.In this paper,poly（six methylene guanidine hydrochloride）（PHMG）,silver nano ion and halogen amine antibacterial agent are three different types of antibacterial agents.They are highly effective broad-spectrum bactericidal and non drug resistant,and then combined with hydrogels in different ways.The specific test contents and results are summarized as follows:In the first chapter,the necessity of bacterial harm and the application of antibacterial materials is described.Then,the research progress of antibacterial hydrogel in recent years is summarized,including the classification of antibacterial hydrogel and the related antibacterial mechanism,and its application in different aspects.In the second chapter,aiming at the problem of poor mechanical properties and bacterial resistance of antibacterial hydrogels,an excellent antibacterial hydrogel was prepared.Firstly,acrylamide（Am）,agar（Agar）,graphene（GO）and tannic acid（TA）were used as main raw materials to form double network hydrogels,and then the antibacterial hydrogels were prepared by binding with PHMG.The structure of the hydrogel was characterized by infrared test.The mechanical properties showed that the elongation at break of the synthesized double network hydrogel increased by about 60%compared with that of the single network,and the compressive strength increased by about 90%.Scanning electron microscopy（SEM）showed that the hydrogel had pore structure and dense pores.The addition of graphene oxide improves the mechanical and thermodynamic properties of the gel.In the antibacterial experiment,the antibacterial hydrogel has an antibacterial rate of over 99.80%against Escherichia coli and Staphylococcus aureus,and has good cell compatibility.In the third chapter,the first step is to remove molybdenum disulfide（Mo S₂）from TA into two dimensional nanosheets of TA-Mo S₂,and then prepare hydrogel with Am by reaction with Ag NO₃ solution.The structure of the hydrogel was characterized by IR.Scanning electron microscopy showed that the addition of Mo S₂made the pore of the antibacterial hydrogel more dense and uniform.Thermogravimetric analysis showed that the thermal stability of the hydrogel improved by adding Mo S₂;swelling test in deionized water and simulated liquid showed that the prepared hydrogel had good swelling properties.The antibacterial experiments and bacteriostatic circle experiments showed that the prepared antibacterial hydrogel could completely inactivate bacteria after contacting with bacteria for 2 h,and the bacteria could not propagate around the antibacterial hydrogel,and the antibacterial properties were excellent.In the fourth chapter,a semi interpenetrating network hydrogel was synthesized by Am and polyvinyl alcohol（PVA）,and then the CC was grafted into the hydrogel by PVA reaction with cyanuric chloride（CC）,and then the antibacterial hydrogel was prepared after chlorination.The structure of the hydrogel was characterized by IR test.The SEM test showed that the synthesized gel had porous structure.Swelling test showed that the equilibrium swelling rate of the synthesized hydrogel was 22.1,has very good water absorption properties.Moreover,the TGA analysis shows that the hydrogel we synthesized has good thermal stability and can still maintain stable performance at high temperatures.In antibacterial experiments and bacteria-inhibiting experiments,the antibacterial gel had excellent antibacterial properties.The performance can inhibit the growth of bacteria,and cause the apoptosis of E.coli and S.aureus in a short time.